The present invention is concerned with riveting tools for use in setting blind rivets of the type which comprises a tubular rivet having a head, and a mandrel which passes through the tubular rivet and comprises a setting head which engages an end face of the tubular rivet remote from its head and a pulling head which is pulled to move the mandrel relative to the rivet to set it. Such rivets are commonly referred to as "double headed rivets".
A tool for setting a double headed rivet requires a nose piece supporting a pulling assembly, adapted to grip the pulling head of the mandrel to Dull the rivet to set the rivet, and an abutment assembly arranged to engage the head of the rivet during its setting. It is necessary that the abutment assembly is capable of moving into an open position to allow the passage of the pulling head of the mandrel past the abutment assembly to engage the pulling assembly and then into a closed position to provide an abutment to engage the head of the rivet.
In a known riveting tool for use with double headed rivets, the abutment assembly comprises a plurality of abutment members extending generally axially of the nosepiece around the pulling assembly and movable between an open position, in which the pulling head of the mandrel may be passed through the abutment assembly to be engaged by the pulling assembly and a closed position in which the abutment members provide an abutment to engage the rivet head. The abutment members are moved radially between their open and closed positions by a sleeve which is moved axially of the tool by a pneumatic piston and cylinder arrangement. This piston and cylinder arrangement is actuated by a sensor which detects when a rivet has been positioned in the pulling assembly and then causes the abutment members to close.
This construction is somewhat complex and expensive.
It is an object of the present invention to provide a riveting tool for use with double headed rivets which is simpler and more economical in construction.